Pelteir\ Thermoelectric Cell Help

Here is some general information on Peltiers, also here. A Peltier (btw: note the spelling) will deliver only a limited voltage which depends on the construction of the element. A commercial Peltier is usually made from several small Peltier cells. each cell can deliver only a limited voltage and amperage. In order to increase the power of a Peltier element, many of these cells are connected either in series or in parallel, or both.
If the cells are in series, the voltage at the terminals increases, but the current stays small.
If the cells are in parallel, the voltage stays small but the current increases.
If they are connected in series and parallel, both voltage and current increase, but to a lesser extend.
And power , as Raven already stated, is V*I.

It were best if you had access to the Peltier element's datasheet. If not, measure the open circuit voltage and the short circuit current to get at least a feeling for the corner characteristics of the element.

If you're going to buy Peltier elements, you need to specify your requirements, but you will still be hard pressed to find data for reverse operation of a Peltier element (i.e. generate power from thermal difference). In a first approximation, for any given temperature difference you will not be able to generate as much electrical power as you need to generate that temperature difference from electrical energy (the latter being routinely stated in the datasheet).